Selecting Good Monitor Speaker can be all ways serious topic for Engineer and Mixer.
when I started my career as an Engineer back in 80’s, Large Monitor Speaker was the main Monitor speaker used by Engineer/Mixer.
Small Speaker were there, just used to check for the downscale mix such as AM radio
YAMAHA NS-10M were just introduced, but no one in America were giving good impression to this Speaker but New york Top engineer/mixer.
No body knew how to use this Ear hurting super MID boosted with NO bass Speaker.
The NY engineer Made many HITs albums, placing TISSUE PAPAER on tweeter to attenuate the viscous High frequency
but soon after, NS10 was all over the world.
Driving it with MOS-FET 500W or more per channel Power Amp (way above the manufacture’s recommendation)
everybody was Playing SOOO!! LOUD (as I was) blowing up the Unit and replacing the parts were almost daily affair. like changing the light-bulbs in toilet
take that MIX to mastering house. they all lacks same frequency to be added by mastering engineer was also daily job.
but it was the trends

Soon after late 80’s, wide range near field monitor was introduced. such as GENELC, self powered monitor become most popular for more than 10 years.
Now these days, there are NO other than self powered Monitor Speaker is available is now in Market.
It’s true globalization.

the advantage for Self Powered Speaker was where ever the Studio you go, we hear the Speaker/Amp Sound only.
room effect was minimum matter.
disadvantage is they all sounds same.(some of them are beaten to death)

last year, I have changed my Power Amp from VTL (tube amp) to CHORDS electronics (Hi -Speed FET ) for
My long partner PRO-AC studio 100.
it is true experience that Amplifier do makes big change to Monitoring.
After using this new amp for 6 month, I have realized and reached to New Style of Mixing Technics were required.

working with custom Monitor is like tuning Race Car Engine
makes more motivation to new way of approaching.
It’s more fun than just working with self contained whatever the given same old sounds.